COLUMBUS, Ohio — A condemned obese killer should be spared because of lingering doubts about his “legal and moral guilt” and the conduct of defense and prosecution lawyers at trial, his attorneys told the state Parole Board on Thursday in a bid for clemency focusing on his innocence, not his weight.

Death row inmate Ronald Post is fighting his January execution on the grounds that he is so fat he can’t be humanely executed and will suffer cruel and unusual punishment as the state struggles to find his veins or give him enough drugs to put someone his size to death.

That argument is in the federal courts, while the 450-pound Post pursues an innocence claim unrelated to his weight before the parole board. The panel considers requests for mercy before making a recommendation to Gov. John Kasich, who has the final say.

Attorneys for Post made presentations to the parole board Thursday followed by prosecutors from Lorain County and the attorney general’s office.

Post, 53, was sentenced to die for the 1983 shooting of Elyria motel clerk Helen Vantz during a robbery. Vantz’ sons, William and Michael, both attended Thursday’s hearing.

At a break, both said they believe firmly in Post’s guilt. William Vantz also had harsh words for Post’s obesity claim.

“It’s just another way for a coward to try and get out of what debt he owes to society,” Vantz said.

The long-held presumption that Post confessed to the murder to several people has been falsely exaggerated, Post’s attorneys argue. Post admitted involvement in the crime as the get-away driver to a police informant but did not admit to the killing.

“Sure ain’t no murderer,” Post told that informant, according to Post’s clemency filing.

Doubt about Post’s guilt lingers because of the involvement of two other men in the shooting, Post’s attorneys argue. Post pleaded no contest to the crime on the advice of his attorney in expectation he would receive a life sentence, the attorneys argue. Even after his plea, he told a psychologist “he was not a murderer.”

The attorneys also argue that prosecutors misrepresented to the judge that Post had confessed to sole involvement in Vantz’s death.

They also say a police detective served as a “double agent” on the case, performing a lie detector test on Post for the defense team while working for the state to perform a similar test on an alleged conspirator in the motel shooting. The detective, “an agent of Post’s defense team, violated a basic duty of loyalty and confidentiality to Post,” the inmate’s attorneys said.

“Lingering doubts exist about the degree of Ronald Post’s legal and moral guilt,” public defenders Joe Wilhelm and Rachel Troutman told the board in a written request for mercy.

“The death penalty should be reserved for cases where proof of guilt is reliable and the legal system produced a just result,” they said. “Neither criteria is met in this case.”

The Lorain County prosecutor argues that Post was the killer and as evidence points to Post’s written no-contest plea in which he acknowledged responsibility for the crime.

That admission is “a compelling reason” why the board should reject clemency, Lorain County prosecutor Dennis Will said in a filing to the board before the hearing.

“Even though some of Post’s personal admissions of criminal actions did not include an express and explicit personal admission that he was the shooter of Helen Vantz, all of Post’s admissions amount to a confession by Post that he committed crimes at the Slumber Inn,” Will wrote.

He also noted that Post signed a document prepared by the detective who conducted the lie detector test acknowledging he killed Vantz.

A federal judge plans a hearing later this month on Post’s obesity claims.

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